Liquid food or beverage preparation machines are becoming very popular whether at home or in offices. For instance, there are machines for the preparation of beverages such as coffee, tea, soup or other similar beverages, in which at least one ingredient of the desired beverage, for example ground coffee, is supplied within a capsule or pod into a capsule or pod extraction chamber of the machine.
The use of capsules or pods, such as plastic and/or aluminium-based capsules or pods for the preparation of beverages has many advantages. Capsules or pods, in particular aluminium-based capsules or pods, are hermetic or gas tight and thus can protect the beverage ingredient effectively during an extended period of time against the environment such as air, humidity or light, before use of the ingredient. Thus such capsules and pods prevent premature degradation of the ingredient. Furthermore, capsules or pods of a beverage ingredient are easy to handle, hygienic, and their use involves less cleaning of the beverage preparation machine, in particular no significant part of the machine's extraction chamber comes into contact with the beverage ingredient contained in the capsule or pod during the extraction process.
Capsules or pods are usually inserted individually into the machine's extraction chamber, manually or automatically from a capsule or pod stack. Hot or cold water is then passed through the capsule or pod for brewing or otherwise extracting the ingredient(s) contained within the capsule or pod and form the desired beverage. The prepared beverage is supplied via an outlet of the machine into a cup, mug or other receptacle to the user.
Used capsules or pods may either be removed individually from the liquid food or beverage preparation machine after each preparation cycle or they may be collected in a machine's used capsule or pod receptacle for instance as mentioned in EP 1 731 065.
Typically, the capsule or pod receptacle is located underneath the capsule or pod chamber so that the capsules or pods may fall by gravity into the receptacle upon extraction. In the latter case, the receptacle has to be emptied by the user when full. The receptacle may be a drawer-type removable receptacle located in a seat of the beverage preparation machine typically under the extraction chamber. The used capsule or pod receptacle may be slid in and out of the machine's housing.
A problem may arise with such capsule or pod receptacles, in particular in conjunction with rigid capsules or pods, when used capsules or pods accumulate in the receptacle to form a heap of capsules or pods whose top extends above the receptacle in such a manner to come into conflict with the housing when the receptacle is slid out of the machine's housing for emptying.
A solution to avoid the jamming of the receptacle by used capsules or pods is to provide an optical level detector for measuring the level of capsules or pods in the used capsule or pod receptacle and inviting the user to empty the receptacle when the level of capsules or pods comes close to the level of the machine's housing. Another solution involves counting the number of capsule or pod extractions after emptying the receptacle and inviting the user to empty the receptacle after a predetermined number of capsules or pods has been collected, an excess of which may possibly cause jamming.
A drawback with the level detector system involves the use of expensive electronic detectors, in particular optical detectors. Furthermore, since the accumulated capsules or pods naturally form a heap in the receptacle a waste of space is usually also involved around this heap. A drawback of the capsule or pod counting system lies in the fact that, in order to avoid jamming at all time, it is necessary to set a maximum number of collectible capsules or pods in the receptacle that will often lead to a poor filling of the receptacle at the time when the user will be invited to re-empty the receptacle and to an even greater waste of space around the heap of collected capsules or pods in the receptacle than with the above described level detector.
Hence, there is still a need to provide an inexpensive simple solution for avoiding jamming of a used capsule or pod receptacle in a liquid food or beverage machine.